The vending machine is how to operate, a very detailed said

The vending machine is the core of single chip microcomputer, does not use PLC! I have seen the single chip microcomputer are: 1, MOTOROLA MC68HC908GP32CP2, fly and P87C52EFAA vending machines have their own special communication protocol, Europe and the United States series of 'the MDB, Japan and South Korea series for' VCCS, not 232, 485, CAN communication protocol. The main control board, COINS, paper money taker manager ( Identify receiving, change) Between all follow this agreement, with series ( Europe and the United States or Japan and South Korea series) Versatility, not only communication protocol, even the installation size, same plug. That is, you can do the fuselage, shipment etc, purchase A card board, B card paper, card COINS (C Can use the same manufacturer, of course) So that all can work normally. When conditions have gradually developed control board, paper money, COINS. At present most of the vending machine in China are Europe and the United States series, using the MDB communication protocol control system. As for the working principle of rough said: when available, identification to receive money, customers choose goods, whether invest sufficiently, internal change is the change, shipment, change. Too much, too complicated, because of the logical relationship in detail can not be said, for example: a, when insufficient internal Angle of 5 COINS, you spent 5 yuan notes to buy 2. 5 yuan or 3 yuan drinks: 1, must find when the machine is set to zero, 2. 5 yuan drinks don't sell, return 5 yuan. 3 yuan drinks sold, found 2 1 yuan coin. 2, when the machine is set to not enough change can also sales, 2. 5 yuan of drinks sold, you click on the two machine to you; 3 yuan drinks sold, found 2 1 yuan coin. Second, when the machine within 5 horn, $1 COINS are not, you spent 5 yuan notes to buy 2. 5 yuan or 3 yuan drinks: 1, must find when the machine is set to zero, 2. Five yuan, three yuan drinks don't sell, return to 5 yuan. 2, when the machine is set to not enough change can also sales, 2. 5 yuan of drinks sold, you click on the two drinks machine to you; 3 yuan drinks sold, 2 yuan balance is always displayed in the machine, you can then invest the money amount after purchase. The vending machine is a mechanical and electrical integration of automation device, on the premise of receiving money entered, button on the touch control input signal is make the controller to start the related position of machinery complete set, the goods to the output. (1) the user will money into the slot, monetary recognizer to put money for identification; (2) the controller according to the amount of information can be selling goods through pick button light is provided to users, by users choose to buy goods; (3) presses the button, the user to select goods corresponding controller receives the key information passed by, driving the corresponding components, the user's choice of commodities sold to fetch the mouth; (4) if there is sufficient balance, can continue to buy. Within 15 seconds, the vending machine will automatically find the coin or user rotating work knob, exit the coin. (5) from the refund money mouth coin to complete the deal. Core technology is as follows: programmable controller ( PLC） Based on microprocessor as the core of industrial control device. It will be the traditional relay control system and computer technology together, has a high reliability, flexible, general and easy programming and easy to use, so in recent years in industrial automatic control, electromechanical integration, widely applied to transform traditional industries, etc. PLC manufacturers and product type many, but the basic principle is the same, especially the ladder diagram ( LD) And sequence function diagram ( SFC） PLC program design method of all are the same. Drawings are confidential, the average person can't get. Maybe your goal is to get the secret of this drawing.